Neonatal lupus erythematosus: Discordant disease expression of U 1RNP-positive antibodies in fraternal twins—Is this a subset of neonatal lupus erythematosus or a new distinct syndrome?

• Published in: Journal of the American Academy of Dermatology Vol. 32; no. 5; pp. 858 - 862
• Main Authors: Solomon, Barry A, Laude, Teresita A, Shalita, Alan R
• Format: Journal Article
• Language: English
• Published: Mosby, Inc 1995
• ISSN: 0190-9622; 1097-6787
• DOI: 10.1016/0190-9622(95)91547-8

Neonatal lupus erythematosus (NLE) is an uncommon disease that is manifested by cutaneous lesions, cardiac conduction defects, or both, that appear in utero or shortly after birth. In approximately 95% of patients, anti-Ro antibody (Ro[SS-A]) has been identified and has become the serologic marker for NLE. Since 1987 there have been four reported cases of Ro- and anti-La antibody (La[SS-B])-negative, U 1RNP antibody-positive, NLE. Our affected twin, as well as all other infants with U 1RNP-positive NLE, had cutaneous lesions similar to those in Ro-positive NLE, although they lacked systemic abnormalities, including cardiac conduction defects. HLA typing of mothers with infants with U 1RNP-positive NLE revealed the presence of HLA-DR4, DQw1, or DQw3 phenotypes. Our typing confirms these findings. As with Ro-positive NLE, no distinct HLA associations were demonstrated in the infants. Unlike Ro-positive mothers, all mothers with a U 1RNP-positive infant with NLE had connective tissue disease at the time of the diagnosis and had a different spectrum of disease. We describe the clinical, serologic, and immunogenetic findings in the first reported case of U 1RNP-positive NLE in dizygotic twins in whom the NLE disease expression was discordant.